OG11-49

49.   Many house builders offer rent-to-buy programs that enable a family with insufficient savings for a conventional down payment to be able to move into new housing and to apply part of the rent to a purchase later.

(A) programs that enable a family with insufficient savings for a conventional down payment to be able to move into new housing and to apply

(B) programs that enable a family with insufficient savings for a conventional down payment to move into new housing and to apply

(C) programs; that enables a family with insufficient savings for a conventional down payment to move into new housing, to apply

(D) programs, which enables a family with insufficient savings for a conventional down payment to move into new housing, applying

(E) programs, which enable a family with insufficient savings for a conventional down payment to be able to move into new housing, applying

Rhetorical construction

In a lengthy sentence consisting of many phrases, it is essential to determine which phrases and words are necessary to the sentence and which words may be eliminated because they are unnecessary. The relative pronoun that correctly refers to programs and introduces the subordinate clause; family is followed by two phrases that are clear and correct. To be able to move, however, is needlessly wordy, repeating the meaning of enable, and can be reduced to to move. This creates a parallel construction in which programs ... enable a family ... to move ... and to apply.

A     To be able to move is wordy; to apply is not logically parallel to the infinitive phrase (able) to move

B      Correct. In this sentence, eliminating the wordy construction to be able allows to move to be parallel to to apply.

C     Using a semicolon here causes that to refer too broadly o the entire previous clause rather than specifically to programs, the two infinitives should be joined by the conjunction and, not separated by a comma

D     The restrictive clause following programs defines programs and must be followed by that; which incorrectly introduces a nonrestrictive clause, set off in a pair of commas, containing relevant but not critical information; enables does not agree with the plural subject

E      That introduces a restrictive clause that defines programs; which introduces a nonrestrictive clause, set off by a pair of commas, that may be dropped from the sentence; that is required here because the clause defines programs

The correct answer is B.

A项两个不定式不平行的原因是否在于一个是(enable) to apply,另一个是(be able) to move呢？？拜请大侠不吝赐教～～～

如果去掉apply 前的 to， 则apply会引起歧义，造成apply和enable平行。

这在逻辑上是错的。所以应该加上to。